In the endless quest to substitute the carbohydrates I love, almonds have become a much bigger part of my diet, mostly in the form of almond meal. I also find myself snacking on roasted almonds during the week. 1 ounce of almonds has about 3 grams net carbs (net carbs = total carbs less fiber) which makes it one of the best nuts for carb sensitive people.
Almond meal can be used in place of flour in a lot of recipes. The trick is to make things that do not utilize the gluten component in flour much. So, pancakes, cookies, biscuits, cakes, quickbreads, all work ok with some adjustments to the leavening components. I tend to use slightly more baking powder, and beat the egg whites separately. Sometimes substituting seltzer for some of the liquid as the last added ingredient helps too. If you want to make something more bread like, gluten may be added back in as long as you're not gluten-sensitive. I've read that xantham gum is a good substitute, but have yet to try it.
I also use almond meal in place of breadcrumbs. Tossing it in a plastic bag with some seasonings and parmesan makes a great breading, or topping for casseroles and veggies. With some egg for binding it seems to stand up well to frying too.
So far, the best place to buy it has been Trader Joe's. They sell it by the one-pound bag for $3.99. For cakes, and quickbreads I like to sift it a bit, but a word of warning: Do not attempt to sift with a modern sifter (the type with the rotating discs on multi-level screens). You will quickly ruin the sifter. Use an antique hoop-style sifter, or a mill.
Some searching online will yield a bounty of almond-meal recipes for cookies, cakes, etc. For sweetener I usually use Splenda, but I'm trying stevia now. So far so good. Enjoy!